From 512f2cc9c49d585b566b3f5200b85748359b4b1e Mon Sep 17 00:00:00 2001
From: Kegan Dougal <kegan@matrix.org>
Date: Tue, 23 Sep 2014 12:22:14 +0100
Subject: [PATCH] Fix SYWEB-8 : Buggy tab-complete.

The first red blink was caused by an uninitialised search index. There is no
caching of entries, since this then wouldn't update if someone joined/left
during the tab. Instead, set to search index to MAX_VALUE then fix it to a
valid index AFTER the search is complete. Also ditched trailing space on ": ".
---
 webclient/room/room-directive.js | 59 ++++++++++++++++++++++----------
 1 file changed, 40 insertions(+), 19 deletions(-)

diff --git a/webclient/room/room-directive.js b/webclient/room/room-directive.js
index e033b003e..8db4cb5d9 100644
--- a/webclient/room/room-directive.js
+++ b/webclient/room/room-directive.js
@@ -21,39 +21,53 @@ angular.module('RoomController')
     return function (scope, element, attrs) {
         element.bind("keydown keypress", function (event) {
             // console.log("event: " + event.which);
-            if (event.which === 9) {
+            var TAB = 9;
+            var SHIFT = 16;
+            var keypressCode = event.which;
+            if (keypressCode === TAB) {
                 if (!scope.tabCompleting) { // cache our starting text
-                    // console.log("caching " + element[0].value);
                     scope.tabCompleteOriginal = element[0].value;
                     scope.tabCompleting = true;
+                    scope.tabCompleteIndex = 0;
                 }
                 
+                // loop in the right direction
                 if (event.shiftKey) {
                     scope.tabCompleteIndex--;
                     if (scope.tabCompleteIndex < 0) {
-                        scope.tabCompleteIndex = 0;
+                        // wrap to the last search match, and fix up to a real
+                        // index value after we've matched
+                        scope.tabCompleteIndex = Number.MAX_VALUE;
                     }
                 }
                 else {
                     scope.tabCompleteIndex++;
                 }
                 
+
                 var searchIndex = 0;
                 var targetIndex = scope.tabCompleteIndex;
                 var text = scope.tabCompleteOriginal;
                 
-                // console.log("targetIndex: " + targetIndex + ", text=" + text);
+                // console.log("targetIndex: " + targetIndex + ", 
+                // text=" + text);
                                     
                 // FIXME: use the correct regexp to recognise userIDs
+                // XXX: I don't really know what the point of this is. You
+                // WANT to match freeform text given you want to match display
+                // names AND user IDs. Surely you just want to get the last
+                // word out of the input text and that's that?
+                // Am I missing something here? -- Kegan
                 var search = /@?([a-zA-Z0-9_\-:\.]+)$/.exec(text);
-                if (targetIndex === 0) {
-                    element[0].value = text;
-                    
-                    // Force angular to wake up and update the input ng-model by firing up input event
+
+                if (targetIndex === 0) { // 0 is always the original text
+                    element[0].value = text;                    
+                    // Force angular to wake up and update the input ng-model 
+                    // by firing up input event
                     angular.element(element[0]).triggerHandler('input');
                 }
                 else if (search && search[1]) {
-                    // console.log("search found: " + search);
+                    // console.log("search found: " + search+" from "+text);
                     var expansion;
                     
                     // FIXME: could do better than linear search here
@@ -68,6 +82,7 @@ angular.module('RoomController')
                     if (searchIndex < targetIndex) { // then search raw mxids
                         angular.forEach(scope.members, function(item, name) {
                             if (searchIndex < targetIndex) {
+                                // === 1 because mxids are @username
                                 if (name.toLowerCase().indexOf(search[1].toLowerCase()) === 1) {
                                     expansion = name;
                                     searchIndex++;
@@ -76,18 +91,22 @@ angular.module('RoomController')
                         });
                     }
                     
-                    if (searchIndex === targetIndex) {
-                        // xchat-style tab complete
+                    if (searchIndex === targetIndex || 
+                            targetIndex === Number.MAX_VALUE) {
+                        // xchat-style tab complete, add a colon if tab 
+                        // completing at the start of the text
                         if (search[0].length === text.length)
-                            expansion += " : ";
+                            expansion += ": ";
                         else
                             expansion += " ";
                         element[0].value = text.replace(/@?([a-zA-Z0-9_\-:\.]+)$/, expansion);
                         // cancel blink
                         element[0].className = "";     
-                        
-                        // Force angular to wake up and update the input ng-model by firing up input event
-                        angular.element(element[0]).triggerHandler('input');
+                        if (targetIndex === Number.MAX_VALUE) {
+                            // wrap the index around to the last index found
+                            scope.tabCompleteIndex = searchIndex;
+                            targetIndex = searchIndex;
+                        }
                     }
                     else {
                         // console.log("wrapped!");
@@ -97,17 +116,19 @@ angular.module('RoomController')
                         }, 150);
                         element[0].value = text;
                         scope.tabCompleteIndex = 0;
-                        
-                        // Force angular to wake up and update the input ng-model by firing up input event
-                        angular.element(element[0]).triggerHandler('input');
                     }
+
+                    // Force angular to wak up and update the input ng-model by
+                    // firing up input event
+                    angular.element(element[0]).triggerHandler('input');
                 }
                 else {
                     scope.tabCompleteIndex = 0;
                 }
+                // prevent the default TAB operation (typically focus shifting)
                 event.preventDefault();
             }
-            else if (event.which !== 16 && scope.tabCompleting) {
+            else if (keypressCode !== SHIFT && scope.tabCompleting) {
                 scope.tabCompleting = false;
                 scope.tabCompleteIndex = 0;
             }